Watching Waves on the Nanoscale

It’s tough to simulate nonlinear wave dynamics, so scientists often test theories in wave flumes, where they can create more controlled waves than what we see in the wild. But conventional wave flumes are big–meters-long, complicated equipment–and can only test a small range of conditions. To reach more extreme nonlinear dynamics, researchers have turned to a chip-based approach. These 100-micron-long wave flumes carry a film of superfluid helium less than 7 nanometers thick. But despite that tiny size, the system can reach levels of nonlinearity five orders of magnitude greater than their full-sized counterparts. (Image and research credit: M. Reeves et al.; via Physics Today)

Capturing the "second sound" wave:
#quantumphysics #thermodynamics #ultracold #superfluid #research #innovation #science
♨️

https://www.popularmechanics.com/science/a65938592/second-wave-superfluid-existence-sound/

https://phys.org/news/2025-07-scientists-density-modes-component-fluid.html

"We study #quantumfluids of light, or in other words, optical systems where light behaves like a #superfluid, which are much like…#superconductors." Quentin Glorieux, "The goal…was to see whether it's possible to push this analogy further by creating a mixture of two interacting fluids of light. Mixtures…support rich collective dynamics and offer a new platform for the study of quantum phase transitions, topological structures or even analog gravity."

"Second sound":
#quantumphysics #thermodynamics #superfluid #research #science
🥃

https://www.popularmechanics.com/science/a64093045/second-wave-superfluid-existence/

💾 Even if my #PhD is over, I'm still closing some projects I had begun with my former research group in #Warsaw.

In this one, we've studied #Superfluid currents across three regimes (from #BCS to #UFG) in the presence of an obstacle. If currents are too high, vortices appear in the ring.

I can't yet tell if #Atomtronic circuitry will be developed or practical, but this hints that wires with "spikes" inside might make the currents more stable.

#Physics #HPC

https://link.aps.org/doi/10.1103/PhysRevResearch.7.013225

Massive black holes drag and warp the spacetime around them in extreme ways. Observing these effects firsthand is practically impossible, so physicists look for laboratory-sized analogs that behave similarly. Fluids offer one such avenue, since fluid dynamics mimics gravity if the fluid viscosity is low enough. To chase that near-zero viscosity, experimentalists turned to superfluid helium, a version of liquid helium near absolute zero that flows with virtually no viscosity. At these temperatures, vorticity in the helium shows up as quantized vortices. Normally, these tiny individual vortices repel one another, but a spinning propeller — much like the blades of a blender — draws tens of thousands of these vortices together into a giant quantum vortex.

With that much concentrated vorticity, the team saw interactions between waves and the vortex surface that directly mirrored those seen in black holes. In particular, they detail bound states and black-hole-like ringdown phenomena. Now that the apparatus is up and running, they hope to delve deeper into the mechanics of their faux-black holes. (Image credit: L. Solidoro; research credit: P. Švančara et al.; via Physics World)

https://fyfluiddynamics.com/2024/05/black-holes-in-a-blender/

#astrophysics #blackHole #fluidDynamics #physics #quantumVortex #science #superfluid #superfluidHelium #vortices #vorticity